The Japan Times - Indonesia steps up wildfire fight that sparked hazardous haze

The vast Southeast Asian archipelago has been battling for weeks to contain wildfires and thick smog, which has been drifting to Malaysia, Singapore and the Philippines.

In West Kalimantan province, one of the hardest-hit regions, haze from the blazes plunged air quality to "hazardous" levels, with visibility below one kilometre on Thursday, National Disaster Mitigation Agency spokesman Berton Suar Pelita Panjaitan said.

More than 14,000 firefighters were deployed in the province and managed to put out fires across nearly 430 hectares on Thursday, he added.

"Our attention to West Kalimantan is significant due to burned peatlands, which require longer handling and monitoring, including cooling down, to ensure fire does not reappear."

In Central Kalimantan province, authorities put out fires in a 197-hectare area across the province, Berton said, adding a thermal drone was deployed to identify underground fire spots.

The province recorded an "unhealthy" air quality level, with visibility below 2.5 kilometres, Berton said.

Schools across the two provinces have been shuttered, and classes were held online, he said.

Indonesia has large swathes of tropical peatlands, an ecosystem with layers of partially decomposed organic materials.

They are an important carbon store when wet, but become highly flammable when dry, and fires can smoulder underground and reignite quickly.

In Malaysia, soaring air pollution levels prompted the government to declare an emergency in a region of the Sarawak state on Borneo, the prime minister's office said.

The declaration covers the Serian division in Malaysian Borneo and will see 647 schools closed from Monday until at least the end of next week.

It comes after the Sarawak disaster management committee formally requested the declaration when the Air Pollutant Index (API) in Serian breached the critical threshold of 500, peaking at 519 earlier on Friday.

K.Nakajima--JT